Paper ejection apparatus having a driving wheel moveable with an inner door

ABSTRACT

A paper ejection apparatus of a multifunctional business machine having a driving wheel installed on a rotatable inner door allows the driving wheel to move with the inner door, and therefore provides sufficient space for cartridge replacement when the inner door is opened. A height difference between a platform and an end of a slit of the housing of the multifunctional business machine allows the driving wheel and an exit roller to have an interfering pre-stress in between when the inner door is closed. The driving wheel is not interfered by the exit roller when the inner door is opening, which prevents the driving wheel from deviating, imprecise homing, or even falling when the inner door is opening or closing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a paper ejection apparatus, and more specifically, to a paper ejection apparatus having a driving wheel moveable with an inner door.

2. Description of the Prior Art

Most business machines have paper ejection mechanism generally comprising a star wheel module and an exit roller module disposed on a printing platform. Due to the lack of space at the front of the machine, a scanner module at the top of the business machine should be uncovered for cartridge replacement, which therefore increases relevant elements and also cost of manufacturing. On the other hand, dust is easy to fall into the printing platform during cartridge replacement and brings down the printing quality. Additionally, it is more likely to damage the machine when proceeding drop down test and vibration test on the machine due to the separation of the scanner module and the printer module.

FIG. 1 and FIG. 2 illustrate a prior art paper ejection mechanism 10 disclosed in the U.S. Pat. No. 5,775,824, which places the star wheel 14 on the inner door 12 that can open outward and downward to eject paper 16 during the process of paper ejection as shown in FIG. 2. Such design adds to not only complexity of the transmission assembly of the printer but also complicated job of a user since he/she has to open the scanner module for cartridge replacement. Even worse, when the inner door 12 opens or closes, the star wheel 14 bears to some interference with the exit roller 18 that will easily cause the star wheel 14 to deviate, fall, or unable to home to the original position.

SUMMARY OF THE INVENTION

The present invention provides a paper ejection apparatus having a driving wheel moveable with an inner door. The paper ejection apparatus comprises a housing having a first slit, the housing comprising a platform located at an end of the first slit, forming a height difference between the platform and the first slit; an inner door rotatably connected to the housing, the inner door comprising a guiding shaft located on the platform capable of sliding along the first slit after the inner door is lifted by the height difference when opening the inner door; an exit roller rotatably installed in the housing; and a driving wheel rotatably installed on the inner door for being pushed against by the exit roller with interference when the guiding shaft is located on the platform, a gap existing between the driving wheel and the exit roller when the inner door is lifted by the height difference.

These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 and FIG. 2 are illustrations of a paper ejection mechanism having a star wheel module on it according to the prior art.

FIG. 3 is an illustration of a multifunctional business machine with a paper ejection apparatus having a driving wheel moveable with an inner door according to the present invention.

FIG. 4 and FIG. 5 are illustrations of partial view of the paper ejection apparatus according to the present invention.

FIG. 6 and FIG. 7 are illustrations of partial view when the inner door is opening.

FIG. 8 is an illustration of a perspective view of the inner door and a protrusion on the housing.

FIG. 9 is an illustration of a perspective view of the inner door along with the driving wheel and the housing.

FIG. 10 is an illustration of the driving wheel installed on the inner door through an elastic element.

DETAILED DESCRIPTION

FIG. 3 refers to an illustration of a multifunctional business machine 20 with a paper ejection apparatus having a driving wheel moveable with an inner door according to the present invention. A printer module and a scanner module (inside the housing and not shown) of the multifunctional business machine 20 are assembled together and structure and element usage of a detached scanner module in the prior art is simplified. A user needs only open the cover 22 of the multifunctional business machine 20 and place document on the scanner module for scanning. When the machine 20 needs cartridge replacement, an inner door 52 at the front side of the multifunctional business machine 20 can be opened directly to replace the cartridge 24. This is because the driving wheel of the paper ejection apparatus is directly attached to the inner door 52 and when the inner door 52 opens as in FIG. 3, the driving wheel moves with the inner door 52, providing the multifunctional business machine 20 enough front space for cartridge 24 replacement.

Please refer to FIG. 4 and FIG. 5. FIG. 4 is an illustration of partial view of the paper ejection apparatus 50 having a driving wheel moveable with the inner door 52 according to the present invention. FIG. 5 is the side view of FIG. 4. In the present invention, the driving wheel can be exemplified with star shape, a preferred exemplary embodiment as the star wheel 54 illustrated in the figures herein, or with round shape, and the following content uses the star wheel 54 as description example. The paper ejection apparatus 50 comprises an inner door 52, a star wheel 54 (or a plurality of star wheels in the exemplary embodiment), a housing 56, and an exit roller 58 (or a plurality of exit rollers in the exemplary embodiment and each corresponding to each star wheel). The inner door 52 is rotatably connected to the housing 56.

The housing 56 comprises a first slit 561, a second slit 563, a platform 564, and a spindle hole 562. The platform 564 is located next to an end of the first slit 561 and forms a height difference between the platform 564 and the first slit 561, with the platform 564 and the height difference between the platform 564 and the first slit 561 forming an L shape in the exemplary embodiment. The end of the first slit 561 is higher than the platform 564 in the exemplary embodiment and the first slit 561 and the second slit 563 have an arc shape. The inner door comprises a guiding shaft 521, a rotary shaft 522, and a restoring pin 523. The rotary shaft 522 is rotatably disposed with one end in the spindle hole 562 of the housing 56, making the inner door 52 rotatable about the housing 56. The restoring pin 523 extends through the second slit 563. The guiding shaft 521 located on the platform 564 of the housing 56 and when the inner door 52 is opened and rotating relative to the housing 56, the inner door is first lifted by the height difference and the guiding shaft 521 then slides along the first slit 561. The restoring pin 523 of the inner door 52 slides along the second slit 563 correspondingly when the inner door 52 rotates along the first slit 561.

FIG. 4 and FIG. 5 illustrate a position of the paper ejection apparatus 50 when the multifunctional business machine 20 is ejecting paper 60. The inner door 52 is close relatively to the multifunctional business machine 20. When the paper 60 is ready to eject, the paper 60 goes in between the exit rollers 58 and the star wheel 54 of the paper ejection apparatus 50. The exit rollers 58 (usually made of rubber with high surface elasticity and friction) roll and bring the paper 60 out of the multifunctional business machine 20. The star wheel 54 above the paper 60 rotates when the paper 60 moves forward. A plurality of teeth on the star wheel 54 pushes against the paper 60, generating a certain friction force between the paper 60 and the exit rollers 58 and since the star wheel 54 contacts the paper 60 with the tip of the tooth, the star wheel 54 driving the paper 60 causes much less ink smear on the paper 60. The exit rollers 58 are rotatably installed in the housing 56 and the star wheel 54 is rotatably installed on the inner door 52. Since the star wheel 54 is installed on the inner door 52 via a second elastic element 541 hanging on the frame of the inner door 52, as FIG. 10 shows, the second elastic element 541 is assembled with the star wheel 54 by passing through the star wheel 54 and fixed on the inner door 52 with its two ends, the star wheel 54 is capable of slightly moving close to or away from the inner door 52 besides the free rotation. Therefore, when the inner door 52 is closed as in FIG. 4 and FIG. 5, the star wheel 54 on the inner door 52 of the paper ejection apparatus 50 is interfered by the exit rollers 58 and slightly pushed close to the inner door 52.

When performing cartridge replacement on the multifunctional business machine 20, the inner door 52 is opened for providing enough front space for replacing the cartridge 24, which is shown in FIG. 3.

Please refer to FIG. 6 and FIG. 7. When the inner door 52 of state in FIG. 5 is opened along the direction H, the guiding shaft 521, the rotary shaft 522, and the inner door 52 that comprises the guiding shaft 521 are all lifted by the height difference due to the fact that the height difference exists between the platform 564 and the end of the first slit 561. As FIG. 5 and FIG. 6 show, the star wheel 54 having interference with the exit rollers 58 is lifted by the height difference in the direction V, bringing about a gap between the star wheel 54 and the exit rollers 58 as in FIG. 6. The gap provides a non-interfering distance for the star wheel 54 and the exit rollers 58 while the rotary shaft 522 on the inner door 52 is also lifted slightly in the direction V but still capable of rotating in the spindle hole 562. When the inner door 52 keeps opening outward, the guiding shaft 521 slides along the first slit 561. Since the star wheel 54 has come off interfering with the exit rollers 58, the star wheel 54 is no longer pushed against by the exit rollers 58 and deviation or weak homing of the star wheel 54 is avoided. FIG. 7 is an illustration when the inner door 52 is completely opened.

A first elastic element 565, usually a spring, is disposed between the housing 56 and the inner door 52 with its two ends connected to the housing 56 and the restoring pin 523 of the inner door 52 respectively. As the inner door 52 is opening outward, the restoring pin 523 is lifted in the direction V as in FIG. 6 and sliding along the second slit 563 of the housing 56. The inner door 52 is going through a protrusion 566 on the housing 56 before it is completely opened, as in FIG. 7. Meanwhile the first elastic element 565 between the housing 56 and the restoring pin 523 is stretched and possesses a restoring pulling force in the direction F. However, the protrusion 566 in the FIG. 7 limits the movement of the inner door 52 that won't be pulled back by the first elastic element 565 and will be held steady in the state as in FIG. 7. At the state in FIG. 7, the multifunctional business machine 20 has enough front space for replacing the cartridge 24.

FIG. 8 refers to another perspective view of the protrusion 566 on the housing 56 and the inner door 52 as in FIG. 7. FIG. 9 refers to another perspective view of the housing 56 and inner door 52 along with the star wheel 54 moveable with inner door 52.

After finishing the cartridge replacement, the user pushes the inner door 52 toward the direction C and forces the inner door 52 to pass the protrusion 566 of the housing 56. When the inner door 52 passes the protrusion 566, the stretched first elastic element 565 pulls the inner door 52 back in the direction F because the limitation of the protrusion 566 to the inner door 52 vanished. The inner door 52 is going back the state as in FIG. 6 and then as in FIG. 5. At this time, the star wheel 54 again interferes with the exit rollers 58 and has an pre-stress in between, providing the paper ejection apparatus 50 the ability for bringing out the paper 60 between the star wheel 54 and the exit rollers 58 when the inner door 52 is closed.

The paper ejection apparatus disclosed in the present invention having a driving wheel installed on the rotatable inner door allows the driving wheel to move with the inner door, and therefore provides the multifunctional business machine sufficient space for cartridge replacement when the inner door is opened. The height difference between the platform and the end of the slit of the housing of the multifunctional business machine allows the driving wheel and the exit roller to have an interfering pre-stress in between when the inner door is closed. And the driving wheel is not interfered by the exit roller when the inner door is opening, which prevents the driving wheel from deviating, imprecise homing, or even falling when the inner door is opening or closing.

Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. 

1. A paper ejection apparatus having a driving wheel moveable with an inner door, comprising: a housing having a first slit, the housing comprising a platform located at an end of the first slit, forming a height difference between the platform and the first slit; an inner door rotatably connected to the housing, the inner door comprising a guiding shaft located on the platform capable of sliding along the first slit after the inner door is lifted by the height difference when opening the inner door; an exit roller rotatably installed in the housing; and a driving wheel rotatably installed on the inner door for being pushed against by the exit roller with interference when the guiding shaft is located on the platform, a gap existing between the driving wheel and the exit roller when the inner door is lifted by the height difference.
 2. The paper ejection apparatus of claim 1 wherein the gap provides a non-interfering distance for the driving wheel and the exit roller, avoiding the driving wheel from being pushed against by the exit roller when the guiding shaft slides along the first slit.
 3. The paper ejection apparatus of claim 1, further comprising a second elastic element assembled with the driving wheel and fixed on the inner door with the two ends of the second elastic element, the second elastic element allowing the driving wheel installed on the inner door for moving close to or away from the inner door.
 4. The paper ejection apparatus of claim 1 wherein the housing further comprising a spindle hole, the inner door further comprising a rotary shaft with one end rotatably disposed in the spindle hole, the rotary shaft, the guiding shaft, and the driving wheel being lifted by the height difference when the inner door is lifted by the height difference.
 5. The paper ejection apparatus of claim 1 wherein the end of the first slit of the housing is higher than the platform.
 6. The paper ejection apparatus of claim 1 wherein the inner door further comprising a restoring pin, the housing further comprising a second slit, the restoring pin extending through the second slit and sliding along the second slit when the inner door rotates along the first slit.
 7. The paper ejection apparatus of claim 6 wherein the first slit and the second slit have an arc shape.
 8. The paper ejection apparatus of claim 6, further comprising a first elastic element connecting between the restoring pin and the housing for pulling the inner door.
 9. The paper ejection apparatus of claim 8 wherein the first elastic element is a spring.
 10. The paper ejection apparatus of claim 1 wherein the housing further comprising a protrusion for holding the inner door.
 11. The paper ejection apparatus of claim 1 wherein the driving wheel is a star wheel.
 12. The paper ejection apparatus of claim 1 wherein the driving wheel is a round wheel.
 13. The paper ejection apparatus of claim 1 wherein the platform and the height difference between the platform and the first slit form an L shape. 